Study on the static and fatigue performance of MCL-shaped shear connectors

Abstract

Seven specimens were prefabricated and conducted in the static and fatigue tests to investigate the static mechanical properties and fatigue performance of the MCL (modified clothoid) shape composite dowels. The failure mode, ultimate carrying capacity, shear stiffness, relative slippage, stiffness degradation and residual load-bearing capacity were studied. Additionally, a theoretical model for calculating the residual load-bearing capacity was proposed. Results showed that the failure mode of the specimens under static and fatigue loads is the concrete shear failure. The failure process included the following stages: the bonding failure, yielding of penetrated bar and concrete shear failure. During fatigue test, the static stiffness of the MCL-shaped composite dowel increased initially, then decreased linearly, and dropped abruptly in the final stage. The results obtained from the theoretical model agreed well with the experimental findings.